//-- getelementbyid wrapper
function $(_id) {
    if (document.getElementById) return document.getElementById(_id);
    if (document.all)            return document.all[_id];
    return false;
}

//-- toggle element display
function toggle(_id) {
    
    obj = $(_id);
    
    if (obj.style.display == "block") {
        obj.style.display = "none";
    } else {
        obj.style.display = "block";
    }
}
    
function openPopup(_url) {
    var w = window.open(_url, "popup", "width=420,height=500");
    w.focus();
}